EP3341263B1 - Clamping device of an adjustable steering column for motor vehicles - Google Patents

Description

The invention relates to a clamping device of an adjustable steering column for motor vehicles, in which a carrier connected to the vehicle chassis is connected to two steering column comprehensive jaws, between which a longitudinally and / or vertically adjustable, a steering shaft rotatably supporting jacket tube is clamped to the steering column, with a clamping bolt connecting the two clamping jaws, which cooperates with a clamping device arranged on at least one of the two clamping jaws such that when the clamping bolt is rotated about the pin axis in the closing direction, the tightening device clamps the jacket tube between the two clamping jaws and upon rotation in the opening direction the clamping jaws releases, so that the jacket tube is adjustable.

In such clamping devices, the problem arises that a non-rotatably connected to the clamping bolt operating lever must apply the force required for the clamping of the jaws in a movement in the closing direction. During a movement of the clamping lever in the opening direction, the said forces act in the reverse direction on the actuating lever, which therefore can be released from the handle of the operator and can bounce against a stop in the opening direction. As a result, the life of the clamping device is reduced and there are sounds that are perceived as unpleasant.

To avoid the above problem, damping devices are known which damp the movement of the actuating lever from the closed position to the open position and avoid noise.

From the EP 2 738 062 A2 a damping device is known in which a cam body, which is arranged on a clamping bolt, a weight balancing spring of the steering column during the transfer to the open lever position further biases and thus realizes a damping. Disadvantage of this solution is that the damping of the Höhenverstellposition depends, because the weight compensation spring is biased different degrees in different height adjustment positions.

From the DE 20 2012 102 159 U1 is a damping device with a liquid damper known. The disadvantage of this is the complex structure and the liquid use.

In US2011 / 185839 A1 a generic clamping device is disclosed.

The object of the invention is to provide an improved damping device for a clamping device of a steering column, which has a simple and inexpensive construction.

The solution according to the invention is that a damping body is arranged on the clamping bolt and is frictionally or elastically connected to the clamping bolt and that the damping body has a radially projecting from the clamping bolt stop tongue which upon rotation of the clamping bolt in the opening direction into contact with the jacket tube or another Part of the steering column comes and prevents rotation of the damping body, so that the rotation of the clamping bolt takes place in the opening direction against the frictional force or elastic force and is damped.

The clamping device according to the invention has the advantage that on the one hand it is independent of the adjustment position of the steering column and also has a simple and inexpensive construction. In the simplest case, the damping body has a bore through which the clamping bolt passes, wherein the diameter of the bore and the Clamping bolt are coordinated so that a relative friction force must be overcome in a relative rotation of the clamping bolt relative to the damping body. As a result of the friction, the elastic energy released by the clamping jaws during the opening process, which leads to an acceleration of the rotational movement of the clamping bolt in the opening direction and of the actuating lever connected to the clamping bolt, is absorbed by friction of the clamping bolt on the damping body, so that the movement is braked and the actuating lever is braked arrives at its stop at a very low speed. This prevents unpleasant noises as well as premature wear of the clamping device.

In an advantageous embodiment, the damping body comprises a plastic or an elastomer. Preferably, the damping body is completely formed from the plastic or the elastomer. This offers the advantage that an improved damping can be achieved.

In an embodiment of the inventive concept it is provided that the elastic connection between the damping body and clamping bolt is achieved by an elastic deformation of the damping body. If the damping body itself is deformed elastically, you need not provided for this purpose additional components.

In a first embodiment of said embodiment, the elastic deformation is a deformation of the stop tongue. The stop tab radially projecting from the clamping bolt can be formed from relatively thin material for this purpose, so that it first applies to the casing tube and bends in a further rotation of the clamping bolt and the damping body, whereby it exerts a torque against the opening direction of rotation on the clamping bolt.

In a second variant of the abovementioned exemplary embodiment, the elastic deformation can also be achieved by widening a region of the damping body which partially surrounds the clamping bolt, in particular by means of a cam of the clamping bolt. In principle, any cross-sectional shape of the bolt which deviates from the circular shape is suitable in conjunction with a correspondingly shaped mating surface of the damping body.

In a particularly preferred embodiment, the clamping device according to the invention can fulfill a further function in addition to the damping effect. For this purpose, the combination of features that the jacket tube is provided with a fixed longitudinal stop and that the damping body has a stop surface at the end of its stop tongue, which is opposite the longitudinal stop with open application device, so that limits a longitudinal displacement of the jacket tube to the vehicle front by stopping the stop surface on the longitudinal stop is, and is closed with the application device above the longitudinal stop, so that in an accident of the motor vehicle, the jacket tube overcoming the frictional force of the jaws in the direction of the vehicle front beyond the longitudinal stop is displaceable.In this embodiment, the already existing stop tongue of the damping body takes over together with an am Jacket tube attached longitudinal stop the function of an on and off switchable limitation of the longitudinal adjustment, which in the case of deliberate longitudinal adjustment by the driver with open Zuspann device is effective and remains switched off with the application device closed, to allow a further displacement of the steering column beyond the normal adjustment range in the longitudinal direction beyond, when it comes to an accident. Clamping devices are well known in the prior art, for example, as a wedge-cam plate application device in which a cam disc connected to the actuating lever is rotated relative to a non-rotatable wedge disc, whereby a clamping stroke causes the clamping jaws to be clamped. Furthermore, tilting pin application devices and ball or roller clamping devices are known from the prior art. However, this exemplary listing of the application devices is not to be understood as a limitation to a type of application devices. The solution according to the invention is thus not limited to the said application devices.

In order to allow rotation of the damper body together with the clamp bolt over a small rotation angle range required for turning off the limitation of the longitudinal displacement and to prevent further rotation of the damper body, even if the clamp bolt continues to rotate in the closing direction, another embodiment the invention, in which the damping body comprises a spring element which projects radially from the clamping bolt in a direction opposite to the stop tongue and abuts the casing tube or another part of the steering column, so that upon rotation of the clamping bolt in the closing direction, the rotational movement of the damping body is limited in that the stop surface of the stop tongue lies outside the effective range of the longitudinal stop. In an advantageous development, the spring element and the damping body as an integral one-piece component, preferably made of plastic, may be formed.

The latter embodiment of the invention with switchable limitation of the longitudinal adjustment of the steering column can be further improved by the measure that the elastic deformation of the Damper body causes an increase in the distance between the pin axis and stop surface of the stop tongue. This measure has the advantage that the stop surface of the stop tongue when closing the application device is always moved first a small distance away from the longitudinal stop in the direction of the pin axis before the stop surface rotates together with the damping body and the clamping bolt, the stop surface upwards out of the Area of the longitudinal stop moves out. If the application device is then opened again, the stop surface first moves downwards into the region of the longitudinal stop by the rotation of the damping body with the clamping bolt and with a further rotation of the clamping bolt in the opening direction, the damping body is prevented from further rotation and deforms elastically, thereby the distance between the stop surface and the pin axis is increased again until the stop surface rests again in extreme cases on the longitudinal stop. Without the shortening of the distance between the pin axis and stop surface during the closing of the application device, the end of the stop tongue could come to lie on opening of the application device on the longitudinal stop so that the stop surface is above the longitudinal stop and thus a limitation of the adjustment in the longitudinal direction is no longer given ,

Figur 1:

eine verstellbare Lenksäule für Kraftfahrzeuge mit einer erfindungsgemäßen Klemmvorrichtung im geschlossenen Zustand;

Figur 2:

dieselbe Lenksäule mit Klemmvorrichtung im geöffneten Zustand;

Figur 3:

eine Lenksäule wie in den Figuren 1 und 2 im Längsschnitt;

Figur 4:

eine Detailansicht mit erfindungsgemäßem Dämpfungskörper einer Klemmvorrichtung im geöffneten Zustand;

Figur 5:

wie Figur 4 im geschlossenen Zustand;

Figur 6:

eine weitere Ausführungsform eines erfindungsgemäßen Dämpfungskörpers einer Klemmvorrichtung im geöffneten Zustand;

Figur 7:

wie Figur 6 im geschlossenen Zustand;

Figur 8:

ein erfindungsgemäßer Dämpfungskörper einer Klemmvorrichtung mit Längsanschlag im geöffneten Zustand;

Figur 9:

wie Figur 8 aber im Übergangsstadium zwischen geöffneten und geschlossenen Zustand;

Figur 10:

wie Figur 8, aber im geschlossenen Zustand.

A simple embodiment of the elastic deformation of the damping body according to the invention is that the stop tongue is bent starting from the region of the clamping bolt in the direction of the casing tube and that when abutment of the stop tongue on the casing tube and further rotation of the clamping bolt in the opening direction, the stop tongue is bent so that the distance of the stop surface of the pin axis increased. Embodiments of the invention are explained below with reference to the drawings. The figures show in detail:

FIG. 1:

an adjustable steering column for motor vehicles with a clamping device according to the invention in the closed state;

FIG. 2:

the same steering column with clamping device in the open state;

FIG. 3:

a steering column like in the Figures 1 and 2 in longitudinal section;

FIG. 4:

a detailed view with inventive damping body of a clamping device in the open state;

FIG. 5:

as FIG. 4 when closed;

FIG. 6:

a further embodiment of a damping body according to the invention a clamping device in the open state;

FIG. 7:

as FIG. 6 when closed;

FIG. 8:

an inventive damping body of a clamping device with longitudinal stop in the open state;

FIG. 9:

as FIG. 8 but in the transitional state between open and closed state;

FIG. 10:

as FIG. 8 but in the closed state.

How to get into the Figures 1 and 2 detects, the steering column shown is fastened to the vehicle chassis, not shown, by means of a carrier 4, which also two jaws 2, 3 carries, which can be clamped together by means of the clamping device according to the invention. It is clamped a jacket tube 1, which rotatably supports a multi-part, in the longitudinal direction 8 telescopically apart and each other mobile steering spindle 5. The jacket tube 1 itself can also be pushed back and forth in the longitudinal direction 8 with the clamping device open. Furthermore, when the clamping device is open, the jacket tube 1 can be moved upwards and downwards in the vertical direction 9. When the jacket tube 1 is clamped by means of the clamping device according to the invention between the jaws 2, 3, it can not be moved in the longitudinal direction 8 or in the vertical direction 9.

The clamping device has a clamping bolt 6, which cooperates with a Zuspannvorrrichtung 7 in order to move the two jaws 2, 3 toward each other, so that they firmly clamp the jacket tube 1 between them. Between the jacket tube 1 and the carrier 4, an energy absorbing device 26 is provided, which cooperates with the application device 7 so that a force flow through the energy absorbing device 26 is interrupted in the open clamping device, so that an adjustment of the jacket tube 1 can take place and a closed clamping device Force flow is given, so that in the case of a vehicle frontal impact, the jacket tube 1 relative to the support 4 with energy absorption, for example by deformation of a bending wire, is displaced.

The clamping bolt 6 connects the two jaws 2, 3 and is connected at its one end 13 with an actuating lever 10 which is rotatable about the pin axis 19. Another end of the clamping bolt 6 is screwed to the jaws 2 by means of a nut 12. The actuating lever 10 acts together with the clamping bolt 6 on a clamping device 7 such that upon rotation of the Operating lever 10 in the closing direction 14 about the pin axis 19, the two jaws 2, 3 firmly clamp the jacket tube 1, and that upon rotation of the actuating lever 10 in the opening direction 15 (counter to the application or closing direction), the jaws 2, 3, the jacket tube 1 for Enable steering column adjustment in the longitudinal direction 8 and in the vertical direction 9.

The FIGS. 4 and 5 show a damping body 11 according to the invention in a first embodiment. The damping body 11 has a through hole 25 through which the clamping bolt 6 passes. In this case, the diameter of the bore 25 and the outer diameter of the clamping bolt 6 is matched to one another such that a clamping connection results and the clamping bolt 6 is frictionally connected to the damping body 11. The damping body 11 has a radially projecting from the clamping bolt 6 stop tongue 16, which comes with a rotation of the clamping bolt 6 in the opening direction 15 in abutment with the jacket tube 1, wherein the rotational movement of the damping body 11 is stopped. If now the clamping bolt 6 rotates further in the opening direction 15, rubs its peripheral surface on the inner surface of the bore 25 of the damping body 11. The rotational movement of the clamping bolt 6 must therefore overcome the frictional force, wherein the kinetic energy of the clamping bolt 6 and the associated actuating lever 10 is absorbed , This leads to a damping of the rotational movement.

A spring element 22 is fastened to the damping body 11 and also to the modified damping body 24 according to an embodiment of the invention described below. The spring element 22 is radially from the clamping bolt 6 from and in the opposite direction as the stop tongue 16 of the damping body 11. The spring element 22 is also located on the jacket tube. 1 and prevents in this way a larger rotational movement of the damping body 11, 24, when the clamping bolt 6 rotates in the closing direction 14. How to get into the FIGS. 5, 7 and 10 detects, the free end of the stop tongue 16 lifts it only a few millimeters from the jacket tube 1.

How to get into the FIGS. 6 and 7 detects, has a modified damping body 24 also has a stop tongue 16, which is designed with a relatively small material thickness, so that it is elastically bendable. The stop tongue 16 is bent starting from the clamping bolt 6 in the direction of the jacket tube 1 out. When the clamping bolt 6 rotates in the opening direction 15, the end of the stop tongue 16 comes into abutment against the casing tube 1 (FIG. FIG. 6 ). Turns the clamping bolt 6 now even further in the opening direction 15, the stop tongue 16 is elastically deformed. Thereby, a portion of the rotational and kinetic energy of the clamping bolt 6 and the actuating lever 10, which in turn comes from the elastic recovery of the jaws 2, 3, used to deform the stop tongue 16, whereby the movement of the clamping bolt 6 and the actuating lever 10 is damped.

In an alternative embodiment which is not shown in detail here, a region 17 enclosing the clamping bolt 6 can be elastically deformed by widening, for example by a cam, not shown, of the clamping bolt 6, which of course can not be completely closed. Again, a portion of the kinetic energy of the clamping bolt 6 and the operating lever 10 would be used by the elastic deformation of the area 17 and the movement will be damped.

One in the FIGS. 8 to 10 illustrated preferred embodiment of the invention provides a longitudinal stop 18, which is mounted on the casing tube 1. The stop tongue 16 of the damping body 24 has at its free end a stop surface 20 which is intended to abut against the longitudinal stop 18 of the jacket tube 1. When the application device 7 as in FIG. 8 is open, the stop surface 20 of the stop tongue 16 is generally at a greater distance from the longitudinal stop 18 of the jacket tube 1. Adjusted the driver now the steering column in the direction 21 to the vehicle front, then shifts the longitudinal stop 18 together with the jacket tube 1 in the direction 21, until it abuts against the stop surface 20 of the stop tongue 16 and prevents further displacement of the jacket tube 1 in the direction 21 to the front of the vehicle.

If, however, like in FIG. 10 shown the application device 7 is closed and locked, the stop tongue 16 is a few millimeters away from the jacket tube 1 above the longitudinal stop 18 and thus outside the effective range of the steering stop 18. If it comes in this situation to a vehicle accident, the jacket tube 1 can continue in the direction 21 to the front of the vehicle move without its longitudinal stop 18 comes into contact with the stop surface 20 of the stop tongue 16. The jacket tube 1 is so after overcoming the frictional force of the jaws 2, 3 in the direction 21 over the longitudinal stop 18 also displaceable, the energy absorbing device 26 may be used to the impact energy that is registered by the driver in the steering wheel, targeted by the Deformation of the energy absorbing element controlled to transform into deformation work. This is an important safety aspect because it prevents the steering column and the steering wheel from being moved towards the driver due to the crash.

The spring 22 ensures in this embodiment that the damping body 24 can rotate as far in the closing direction 14 until the end of its stop tongue 16 is lifted out of the effective range of the longitudinal stop 18 of the jacket tube 1.

In FIG. 9 is an intermediate position between the in FIG. 8 shown full opening of the application device 7 and in FIG. 10 shown complete closure shown. Here it can be seen that due to the above-described elasticity of the stop tongue 16, the stop surface 20 in the partially closed state of the application device 7 has a slight distance (gap) to the longitudinal stop 18 of the jacket tube 1. Turning the clamping bolt 6 out of the in FIG. 9 shown intermediate position in the fully open position of FIG. 8 , the stop tongue 16 deforms by being bent up. In this case, the distance 23 between the pin axis 19 and the longitudinal stop 18 increases, so that the gap between the stop surface 20 of the stop tongue 16 and the longitudinal stop 18 of the jacket tube 1 closes.

The gap is important in the event that in the open state of the application device 7 according to FIG. 8 the steering column and thus the jacket tube 1 is adjusted to the abutment of the longitudinal stop 1 on the stop surface 20. If now the stop tongue 16 would not be deformed elastically when closing the application device 7, said gap could not arise. Rather, the stop tongue 16 would possibly against a occurring between the stop surface 20 and the longitudinal stop 18 frictional force in the closing direction 14, ie move upwards. If the application device 7 is subsequently opened again, it could happen that the end of the stop tongue 16 comes to rest on the upper side of the longitudinal stop 18 and the stop surface 20 could not strike against the longitudinal stop 18. Then However, even in the open state of the application device 7, there would be no limitation on the longitudinal movement of the jacket tube 1 in the direction 21 toward the front of the vehicle and the steering column would be adjustable into an inadmissible region.

To avoid this, the stop tongue 16 of the damping body 24 is designed to be elastic.

LIST OF REFERENCE NUMBERS

1

casing pipe

2

jaws

3

jaws

4

carrier

5

steering shaft

6

clamping bolts

7

application device

8th

longitudinal direction

9

vertical direction

10

actuating lever

11

damping body

12

mother

13

The End

14

closing direction

15

opening direction

16

stop tongue

17

Area

18

longitudinal stop

19

pin axis

20

stop surface

21

Direction / longitudinal displacement

22

spring element

23

distance

24

damping body

25

drilling

Claims (8)

1. Clamping device of an adjustable steering column for motor vehicles, in which a carrier (4) which is securely connected to the vehicle chassis is connected to two clamping jaws (2, 3) which surround the steering column and between which a steering column tube (1) of the steering column which can be longitudinally and/or vertically adjusted and which rotatably supports a steering spindle (5) can be securely clamped, having a clamping pin (6) which connects the two clamping jaws (2, 3) and which cooperates with a clamping retention device (7) which is arranged on at least one of the two clamping jaws (2, 3) in such a manner that, in the event of a rotation of the clamping pin (6) about the pin axis (19) in the closure direction (14), the clamping retention device (7) clamps the steering column tube (1) between the two clamping jaws (2, 3) and, in the event of a rotation in the opening direction (15), releases the clamping jaws (2, 3) so that the steering column tube (1) can be adjusted, characterized in that a damping member (11, 24) is arranged on the clamping pin (6) and is connected to the clamping pin (6) in a frictionally engaging or resilient manner and in that the damping member (11, 24) comprises a stop tongue (16) which protrudes radially from the clamping pin (6) and which, when the clamping pin (6) is rotated in an opening direction (15), moves into abutment with the steering column tube (1) or another component of the steering column and prevents a rotation of the damping member (11, 24) so that the rotation of the clamping pin (6) in an opening direction (15) is carried out counter to the friction force or resilient force and is damped.
2. Clamping device according to Claim 1, characterized in that the resilient connection between the damping member (11, 24) and clamping pin (6) is produced by means of a resilient deformation of the damping member (11).
3. Clamping device according to Claim 2, characterized in that the resilient deformation is a deformation of the stop tongue (16).
4. Clamping device according to Claim 2, characterized in that the resilient deformation is achieved by expanding a region (17) of the damping member (11, 24) partially surrounding the clamping pin (6) by means of a cam of the clamping pin (6).
5. Clamping device according to one of the preceding claims, characterized in that the steering column tube (1) is provided with a fixed longitudinal stop (18) and in that the damping member (24) comprises at the end of the stop tongue (16) thereof a stop face (20) which, when the clamping retention device (7) is open, is opposite the longitudinal stop (18) so that a longitudinal displacement (21) of the steering column tube (1) toward the vehicle front is limited by the stop face (20) stopping against the longitudinal stop (18) and which, when the clamping retention device (7) is closed, is located above the longitudinal stop (18) so that, in the event of an accident of the motor vehicle, the steering column tube (1) can with the friction force of the clamping jaws (2, 3) being overcome be displaced in the direction (21) of the vehicle front beyond the longitudinal stop (18).
6. Clamping device according to Claim 5, characterized in that the damping member (11) comprises a resilient element (22) which protrudes radially from the clamping pin (6) in a direction counter to the stop tongue (16) and lies against the steering column tube (1) or another component of the steering column so that, in the event of a rotation of the clamping pin (6) in the closure direction (14), the rotational movement of the damping member (24) is limited so that the stop face (20) of the stop tongue (16) is located outside the effective region of the longitudinal stop (18).
7. Clamping device according to Claim 5 or 6, characterized in that the resilient deformation of the damping member (24) brings about an increase of the spacing (23) between the pin axis (19) and stop face (20) of the stop tongue (16).
8. Clamping device according to Claim 7, characterized in that the stop tongue (16) is bent from the region of the clamping pin (6) in the direction toward the steering column tube (1) and in that, when the stop tongue (16) is in abutment with the steering column tube (1) and the clamping pin (6) is rotated further in the opening direction (15), the stop tongue (16) is bent up so that the spacing (23) of the stop face (20) from the pin axis (19) is increased.

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